In the field of building decoration, the wall surface of the building is often rough and uneven, which has a bad effect on subsequent plastering processes, such as painting or mud scraping, therefore the rough wall surface needs to be polished. If the rough wall surface is polished well, it will be convenient for the subsequent painting on the wall. However, the existing polishing operations are all conducted through a simple hand-held polishing machine held by the staff, and the rough and uneven wall surface is polished by controlling the polishing head, which leads to high labor intensity, waste of time and labor, and the wall surface is uneven after polishing, thereby affecting the polishing effect and accuracy. What's more, large dust will be produced during polishing, which will do damage to human body, and the spreading dust will lead to inconvenience in subsequent sweeping.